Modified Titanium Implants Satisfy the Demands of Diabetic Osseointegration via Sequential Regulation of Macrophages and Mesenchymal Stem Cells.

The application of titanium (Ti) implants for patients with diabetes mellitus (DM) is still facing a significant challenge due to obstacles such as hyperglycemia, reactive oxygen species (ROS), and chronic inflammation, which hinders osseointegration. To address this issue, a Ti implant with dual functions of regulating polarization of macrophages and facilitating osseointergration is developed via hydrothermal reaction and hydrogel coating. The reactive oxygen species (ROS) and glucose (Glu) responsive hydrogel coating can locally deliver adenosine (ADO) in the early stage of implantation. The controlled release of ADO regulated the phenotype of macrophages, restored oxidative balance, and enhanced mitochondrial function during the early stages of implantation. Subsequently, strontium (Sr) ions will be released to promote osteogenic differentiation and proliferation of mesenchymal stem cells (MSCs), as the hydrogel coating degraded. It eventually leads to bone reconstruction during the late stages, aligning with the biological cascade of bone healing. The modified Ti implants showed effective osteogenesis for bone defects in DM patients, shedding light on the design and biological mechanisms of surface modification. This research offers promising potential for improving the treatment of bone-related complications in diabetic patients.

Glutathione-Responsive and Hydrogen Sulfide Self-Generating Nanocages Based on Self-Weaving Technology To Optimize Cancer Immunotherapy.

As an ideal drug carrier, it should possess high drug loading and encapsulation efficiency and precise drug targeting release. Herein, we utilized a template-guided self-weaving technology of phase-separated silk fibroin (SF) in reverse microemulsion (RME) to fabricate a kind of hyaluronic acid (HA) coated SF nanocage (HA-gNCs) for drug delivery of cancer immunotherapy. Due to the hollow structure, HA-gNCs were capable of simultaneous encapsulation of the anti-inflammatory drug betamethasone phosphate (BetP) and the immune checkpoint blockade (ICB) agent PD-L1 antibody (αPD-L1) efficiently. Another point worth noting was that the thiocarbonate cross-linkers used to strengthen the SF shell of HA-gNCs could be quickly broken by overexpressed glutathione (GSH) to reach responsive drug release inside tumor tissues accompanied by hydrogen sulfide (H2S) production in one step. The synergistic effect of released BetP and generated H2S guaranteed chronological modulation of the immunosuppressive tumor microenvironment (ITME) to amplify the therapeutic effect of αPD-L1 for the growth, metastasis, and recurrence of tumors. This study highlighted the exceptional prospect of HA-gNCs as a self-assistance platform for cancer drug delivery.

Gut Clostridium sporogenes-derived indole propionic acid suppresses osteoclast formation by activating pregnane X receptor.

Bone homeostasis is maintained by osteoclast-mediated bone resorption and osteoblast-mediated bone formation. A dramatic decrease in estrogen levels in postmenopausal women leads to osteoclast overactivation, impaired bone homeostasis, and subsequent bone loss. Changes in the gut microbiome affect bone mineral density. However, the role of the gut microbiome in estrogen deficiency-induced bone loss and its underlying mechanism remain unknown. In this study, we found that the abundance of Clostridium sporogenes (C. spor.) and its derived metabolite, indole propionic acid (IPA), were decreased in ovariectomized (OVX) mice. In vitro assays suggested that IPA suppressed osteoclast differentiation and function. At the molecular level, IPA suppressed receptor activator of nuclear factor kappa-Β ligand (RANKL)-induced pregnane X receptor (PXR) ubiquitination and degradation, leading to increased binding of remaining PXR with P65. In vivo daily IPA administration or repeated C. spor. colonization protected against OVX-induced bone loss. To protect live bacteria from the harsh gastric environment and delay the emptying of orally administered C. spor. from the intestine, a C. spor.-encapsulated silk fibroin (SF) hydrogel system was developed, which achieved bone protection in OVX mice comparable to that achieved with repeated germ transplantation or daily IPA administration. Overall, we found that gut C. spor.-derived IPA was involved in estrogen deficiency-induced osteoclast overactivation by regulating the PXR/P65 complex. The C. spor.-encapsulated SF hydrogel system is a promising tool for combating postmenopausal osteoporosis without the disadvantages of repeated germ transplantation.

Non-Pore Dependent and MMP-9 Responsive Gelatin/Silk Fibroin Composite Microparticles as Universal Delivery Platform for Inhaled Treatment of Lung Cancer.

Developing a drug delivery platform that possesses universal drug loading capacity to meet various requirements of cancer treatment is a challenging yet interesting task. Herein, a self-assembled gelatin/silk fibroin composite (GSC) particle based drug delivery system is developed via microphase separation followed by desolvation process. Thanks to its preassembled microphase stage, this GSC system is suitable for varying types of drugs. The desolvation process fix drugs inside GSC rapidly and densify the GSC structure, thereby achieving efficient drug loading and providing comprehensive protection for loaded drugs. Actually, the size of this brand-new non-pore dependent drug delivery system can be easily adjusted from 100 nm to 20 µm to fit different scenarios. This work selects GSC with 3 µm diameter as the universal inhaled drug delivery platform, which shows an excellent transmucosal penetration and lung retention ability. Additionally, the MMP-9 sensitive degradation property of GSC enhances the targeted efficiency of drugs and reduces side effects. Intestinally, GSC can self-amplify the regulation of innate immunity to reverse the cancerous microenvironment into an antitumor niche, significantly improving the therapeutic effect of drugs. This study of GSC universal drug platform provides a new direction to develop the next-generation of drug delivery system for lung cancer.

Enhanced Immunogenic Cell Death and Antigen Presentation via Engineered Bifidobacterium bifidum to Boost Chemo-immunotherapy.

The immunogenic cell death (ICD) of tumor cells has aroused great interest in the field of immunotherapy, mainly due to the production of plentiful tumor-associated antigens (TAAs) and damage-associated molecule patterns. However, doxorubicin (DOX)-induced tumor-specific T-cell-mediated immune response is usually very weak because of antigen presentation deficiency and the immunosuppressive tumor microenvironment (ITME). Herein, the probiotic Bifidobacterium bifidum (Bi) was covalently modified with DOX-loaded CaP/SiO2 nanoparticles (DNPs@Bi) for tumor therapy. On one hand, the pH-responsive release of DOX could induce chemotherapy and ICD in the ITME. On the other hand, tumor-targeting Bi is able to significantly enhance the presentation of TAAs from B16F10 cells to DCs via Cx43-dependent gap junctions. Due to the combination of enhanced ICD and TAAs presentation, the maturation of DCs and the infiltration of cytotoxic T lymphocytes in the ITME were stimulated. As a result, in vivo antitumor experiments demonstrated that DNPs@Bi prolonged the survival rate and significantly inhibited the tumor progression and metastasis. This strategy of bacterial-driven hypoxia-targeting delivery systems offers a promising approach to tumor chemo-immunotherapy.

Double-drug loading upconversion nanoparticles for monitoring and therapy of a MYC/BCL6-positive double-hit diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is a systemic hematological malignancy. Herein, through whole exome sequencing (WES), we found that DLBCL genome changes and expression characteristics are associated with various immune cells. Lenalidomide (Len) is a leading candidate for the immunomodulatory treatment of multiple myeloma in the clinic. Inspired by lenalidomide as an immunomodulatory drug for the treatment of multiple myeloma, we constructed a multifunctional nanoplatform with therapeutic and imaging properties for DLBCL by co-loading lenalidomide and dexamethasone (Dex) with upconversion nanoparticles using a GSH-sensitive linker (named as UCNPs-Len-Dex). In vitro cell experiments proved that the UCNPs-Len-Dex had good biocompatibility and obvious antitumor efficacy. UCNPs-Len-Dex also exhibited excellent anti-tumor efficacy and imaging properties in vivo. RNA sequencing showed that UCNPs-Len-Dex targeted and activated the E3 ligase of CRBN, resulting in IKZF1/3 degradation, which inhibited MYC/BCL6-positive DLBCL and maintained the stability of the immune microenvironment. Therefore, this study provided a new monitoring and therapeutic synergetic strategy for DLBCL.

Multi-responsive nanotheranostics with enhanced tumor penetration and oxygen self-producing capacities for multimodal synergistic cancer therapy.

Incorporation of multiple functions into one nanoplatform can improve cancer diagnostic efficacy and enhance anti-cancer outcomes. Here, we constructed doxorubicin (DOX)-loaded silk fibroin-based nanoparticles (NPs) with surface functionalization by photosensitizer (N770). The obtained nanotheranostics (N770-DOX@NPs) had desirable particle size (157 nm) and negative surface charge (-25 mV). These NPs presented excellent oxygen-generating capacity and responded to a quadruple of stimuli (acidic solution, reactive oxygen species, glutathione, and hyperthermia). Surface functionalization of DOX@NPs with N770 could endow them with active internalization by cancerous cell lines, but not by normal cells. Furthermore, the intracellular NPs were found to be preferentially retained in mitochondria, which were also efficient for near-infrared (NIR) fluorescence imaging, photothermal imaging, and photoacoustic imaging. Meanwhile, DOX could spontaneously accumulate in the nucleus. Importantly, a mouse test group treated with N770-DOX@NPs plus NIR irradiation achieved the best tumor retardation effect among all treatment groups based on tumor-bearing mouse models and a patient-derived xenograft model, demonstrating the unprecedented therapeutic effects of trimodal imaging-guided mitochondrial phototherapy (photothermal therapy and photodynamic therapy) and chemotherapy. Therefore, the present study brings new insight into the exploitation of an easy-to-use, versatile, and robust nanoplatform for programmable targeting, imaging, and applying synergistic therapy to tumors.

Doxorubicin-loaded polypyrrole nanovesicles for suppressing tumor metastasis through combining photothermotherapy and lymphatic system-targeted chemotherapy.

The lymphatic system provides a main route for the dissemination of most malignancies, which was related to high mortality in cancer patients. Traditional intravenous chemotherapy is of limited effectiveness on lymphatic metastasis due to the difficulty in accessing the lymphatic system. Herein, a novel lymphatic-targeting nanoplatform is prepared by loading doxorubicin (DOX) into sub-50 nm polypyrrole nanovesicles (PPy NVs). The PPy NVs possessed hollow spherical morphologies and a negative surface charge, leading to high drug loading capacity. These vesicles can also convert near-infrared (NIR) light into heat and thus can be used for tumor thermal ablation. DOX loaded PPy NVs (PPy@DOX NVs) along with NIR illumination are highly effective against 4T1 breast cancer cells in vitro. More importantly, following subcutaneous (SC) injection, a direct lymphatic migration of PPy@DOX NVs is confirmed through fluorescence observation of the isolated draining nodes. The acidic conditions in metastatic nodes might subsequently trigger the release of the encapsulated DOX NVs based on their pH-sensitive release profile. In a mouse model bearing 4T1 breast cancer, lymphatic metastases, as well as lung metastases, are significantly inhibited by nanocarrier-mediated trans-lymphatic drug delivery in combination with photothermal ablation. In conclusion, this platform holds great potential in impeding tumor growth and metastasis.

Quadruple-responsive nanoparticle-mediated targeted combination chemotherapy for metastatic breast cancer.

The synergism of combination chemotherapy can only be achieved under specific drug ratios. Herein, hyaluronic acid (HA)-functionalized regenerated silk fibroin-based nanoparticles (NPs) were used to concurrently deliver curcumin (CUR) and 5-fluorouracil (5-FU) at various weight ratios (3.3 : 1, 1.6 : 1, 1.1 : 1, 1 : 1, and 1 : 1.2) to breast tumor cells. The generated HA-CUR/5-FU-NPs were found to have desirable particle sizes (around 200 nm), narrow size distributions, and negative zeta potentials (about -26.0 mV). Interestingly, these NPs showed accelerated drug release rates when they were exposed to buffers that mimicked the multi-hallmarks in the tumor microenvironment (pH/hydrogen peroxide/glutathione/hyaluronidase). The surface functionalization of NPs with HA endowed them with in vitro and in vivo breast tumor-targeting properties. Furthermore, we found that the co-loading of CUR and 5-FU in HA-functionalized NPs exhibited obvious synergistic anti-cancer, pro-apoptotic, and anti-migration effects, and the strongest synergism was found at the CUR/5-FU weight ratio of 1 : 1.2. Most importantly, mice experiments revealed that HA-CUR/5-FU-NPs (1 : 1.2) showed a superior anti-cancer activity against metastatic breast cancer compared to the single drug-loaded NPs and non-functionalized CUR/5-FU-NPs (1 : 1.2). Collectively, these results demonstrate that HA-CUR/5-FU-NPs (1 : 1.2) can be exploited as a robust nanococktail for the treatment of breast cancer and its lung metastasis.

Inhibition of growth and lung metastasis of breast cancer by tumor-homing triple-bioresponsive nanotherapeutics.

Lung metastasis of breast cancer is a leading cause of cancer-related death in women. Herein, we attempted to simultaneously inhibit the growth and lung metastasis of breast cancer by delivering quercetin (QU) using LyP-1-functionalized regenerated silk fibroin-based nanoparticles (NPs). The generated LyP-1-QU-NPs had a desirable diameter (203.2 nm) and a negatively charged surface (-12.7 mV). Interestingly, these NPs exhibited intrinsic responsibilities when triggered by various stimulating factors in the tumor microenvironment (acidic pH, reactive oxygen species, and glutathione). In vitro experiments revealed that the introduction of LyP-1 to the NP surface could significantly increase their cellular uptake efficiencies by 4 T1 cells, and facilitate their accumulation in mitochondria. Moreover, LyP-1-QU-NPs showed the strongest mitochondrial damage effect among all the treatment groups. We also found that LyP-1-QU-NPs not only exhibited excellent pro-apoptotic activities but also presented strong inhibitory effects on cell mobility (migration and invasion) through anti-glycolysis and pro-autophagy. Mice experiments confirmed that LyP-1-QU-NPs could efficiently inhibit the in situ growth of breast tumors and further restrict their lung metastasis. Collectively, our results demonstrate that LyP-1-QU-NPs, which integrates the functions of tumor cell targeting, mitochondria targeting, bioresponsive drug release, pro-apoptosis, and anti-mobility, can be developed as a promising nanotherapeutic for the effective treatment of breast cancer and its lung metastasis.

Multi-responsive nanococktails with programmable targeting capacity for imaging-guided mitochondrial phototherapy combined with chemotherapy.

The integration of multimodal functions into one nanoplatform holds great promise for enhancing anticancer drug action and mitigating adverse effects. Herein, we prepared hyaluronic acid-functionalized regenerated silk fibroin-based nanoparticles (NPs) loading with photosensitizer (NIR770) and doxorubicin (DOX). The resultant HNDNPs had a desirable diameter of 161.0 nm and a negative zeta-potential of -30.5 mV. Interestingly, they showed excellent responses when triggered with various stimuli (acidity, reactive oxygen species, glutathione, hyaluronidase, or hyperthermia). Cell experiments revealed that HNDNPs could be specifically internalized by A549 cells, and efficiently released the payloads into the cytoplasm. Moreover, NIR770 was preferentially retained in mitochondria due to its lipophilic and cationic properties, which exhibited highly efficient photothermal therapy and photodynamic therapy upon near infrared (NIR) irradiation. Meanwhile, DOX molecules were mainly accumulated in the nucleus. Intravenous injection of HNDNPs into mice followed by NIR irradiation provided excellent multimodal imaging (NIR, photothermal, and photoacoustic imaging), almost eliminated the entire tumor, and greatly prolonged mice survival time with no side effects. Our study demonstrates that this HNDNP, which integrates the functions of tumor targeting, on-demand drug release, multimodal imaging, mitochondrial phototherapy, and chemotherapy, can be exploited as a promising nanococktail for imaging-guided synergistic treatment of cancer.

Injectable, Thixotropic, and Multiresponsive Silk Fibroin Hydrogel for Localized and Synergistic Tumor Therapy.

Combinational cancer therapy offers a promising strategy to overcome the limitations of single-drug treatment, including limited therapeutic efficacy, serious side effects, and low survival rate. Injectable silk fibroin (SF) hydrogel has emerged as an effective platform for localized treatment. Herein, hydrophilic SF (HSF) was extracted from regenerated SF and self-assembled into hydrogel within 2-6 h. The obtained HSF hydrogel showed obvious viscoelasticity, thixotropic behavior, and self-healing performance. Interestingly, this hydrogel also exhibited excellent stimuli-responsive drug release profiles when triggered by multiple factors (acidity, reactive oxygen species, glutathione, hyperthermia, and near-infrared (NIR)), suggesting that it could achieve spatially and temporally on-demand drug release in response to tumor microenvironment and extra-tumor NIR irradiation. Importantly, intratumoral injection of doxorubicin (DOX)/Cy7-loaded HSF-based hydrogel (DOX/Cy7-hydrogel) plus NIR irradiation exerted the best antitumor effect among all the treatment groups, revealing the strong synergistic effects of chemo/photothermal/photodynamic therapy. It is worth noting that this DOX/Cy7-hydrogel could almost eliminate the entire tumor masses, significantly prolonging the survival time of tumor-bearing mice over 60 days without detectable adverse effects. Collectively, our findings suggest that this injectable DOX/Cy7-hydrogel with thixotropic and multistimuli responsive properties could be developed as a promising platform for localized and synergistic treatment of cancer.

Silk fibroin-based nanotherapeutics: application in the treatment of colonic diseases.

The incidence of colonic diseases (e.g., inflammatory bowel diseases and colon cancer) is rapidly rising. Nanotherapeutic has been considered as a promising strategy in the treatment of colonic diseases. Silk fibroin (SF) has been widely used as a drug-carrier matrix. Interestingly, SF-based nanoparticles (SFNPs) have intrinsic anti-inflammatory activity, wound healing capacity and lysosomal environment-responsive drug-release property. With further investigations, the sequences of SF molecules could be precisely modified through chemical reactions or transgenic techniques to greatly improve the properties of SFNPs. Here, we review recent advances in the application of SFNPs toward the treatment of colonic diseases. We also discuss future developments that might improve the anti-inflammatory and anti-colon cancer activities of SF-based nanotherapeutics.

Modulation of drug release by decoration with Pluronic F127 to improve anti-colon cancer activity of electrospun fibrous meshes.

Applications of fibrous meshes for localized chemotherapy have been limited by the lack of optimal carriers that are capable of releasing sufficient drug locally. To overcome this obstacle, we introduced Pluronic F127 (PF127) to the camptothecin (CPT)-loaded poly(lactic acid/glycolic acid) (PLGA) electrospun fibrous meshes, abbreviated as PPC, for modulation of drug release. These PPC meshes had smooth surface and high drug loading (5.6-6.8%). Addition of PF127 obviously improved the hydrophilicity of the meshes. Interestingly, the CPT release rate of PPC meshes was significantly higher than that of CPT-loaded PLGA (PLGA-CPT) meshes. Most importantly, incorporation of PF127 in the meshes led to significant reduction in the CT-26 viability compared to PLGA-CPT mesh. The improved anticancer effects of PPC meshes were mainly due to the induction of apoptosis in CT-26 cells. These findings suggest that PPC mesh could be a promising implantable system that may enhance the therapeutic efficacy and prevent tumor recurrence after surgical resection.

Facile Fabrication of Oxidation-Responsive Polymeric Nanoparticles for Effective Anticancer Drug Delivery.

Reactive oxygen species (ROS) are highly overproduced in cancerous tissues, and thus oxidation-responsive nanoparticles (NPs) have emerged as a promising drug carrier for cancer-targeted drug delivery. In this study, we successfully synthesized poly(vanillyl alcohol- co-oxalate) (PVAX) polymer with an excellent ROS-responsive capacity. A well-established emulsion-solvent evaporation method was used to fabricate PVAX-based curcumin (CUR)-loaded NPs (PVAX-NPs) and their counterparts (poly(lactic- co-glycolic acid)-based CUR-loaded NPs, PLGA-NPs). It was found that these NPs had a hydrodynamic particle size of approximately 245 nm, narrow size distribution (polydispersity index less than 0.1), negative zeta potential (around -18 mV), smooth surface appearance, and high drug encapsulation efficiency. Moreover, we found that the CUR release rate of PVAX-NPs was greatly increased in the presence of a hydrogen peroxide-rich environment due to the cleavage of polyoxalate ester bonds in PVAX polymer, resulting in the evenly distribution of CUR within the whole cancer cells. More importantly, PVAX-NPs exhibited much stronger anticancer activities and pro-apoptotic capacities than PLGA-NPs both in vitro and in vivo. These results clearly demonstrate that these ROS-responsive PVAX-NPs can be exploited as a robust anticancer drug delivery platform in chemotherapy.